JPH0345495B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power switchgear, and more particularly to an improvement in an arcing horn provided on a movable contact.

This type of device will be explained below with reference to the drawings.

1, 2, and 3, reference numeral 1 indicates an arc extinguishing arc box made of a heat-resistant material, grit 2 made of magnetic metal, and commutator plate 3.
are arranged and fixed in accordance with the number of phases of the electrical circuit to be opened and closed. 4 is a crossbar, 5 is a movable contact, and 5A is an arc horn having a portion parallel to the movable contact 5, which is used to transfer one end of the arc that has moved from the movable contact 6 to the movable contact 5. 6 is a movable contact attached to both ends of the movable contact 5, 7 is a movable contact presser, 8 is a presser spring support, 9 is a contact spring, and 10 is a stopper. The contact spring 9 is compressed and fixed between the lower part of the stopper 10 and the lower end of the presser spring support 8, and the upper end of the presser spring support 8, the upper surface of the movable contact holder 7, and the upper surface of the movable contact 5. and the lower surface of the movable contact holder 7 are assembled so as to be in contact with each other. 11 is a base made of electrical insulator, 12 is a terminal fixed to the top of base 11 with a screw, and 13 is a U-shaped fixed contact screwed to the top surface of terminal 12; A contact 14 is attached. 15 is an arc runner fixed to the fixed contact 13.

The movable contact is connected to a built-in well-known electromagnetic drive device via a movable contact spring 9.

Such contact mechanisms are provided symmetrically with respect to the A-A cross section, and are arranged corresponding to the number of phases of the electrical circuits that open and close in a direction perpendicular to the plane of the paper.

2 is a perspective view schematically showing the commutation plate 3, movable contact 5, and movable contact 6, which are the main parts of FIG. 1, and also the fixed contact 13, fixed contact 14, and arc runner in FIG. When the part 15 is enlarged, it looks like Fig. 3 a and b. In particular, the arc runner 15 has a first side 15a that is substantially parallel to the fixed contact 13 and is provided on the movable contact side with a space therebetween, and the arc runner 15 connects the movable contact from the side opposite to the fixed contact of the first side 15a. It has a second side 15b that extends in a perpendicular direction with a space between it and the child 5. Moreover, the fixed contact side of the first side 15a has a notch 1 that allows the movable contact 6 to move up and down.
It is electrically connected to the fixed contact 13 via a hanging portion 15d having a diameter 5c.

In such a power switchgear, when the fixed contact 14 and the movable contact 6 are opened and separated, one end of the arc generated between the two contacts flows from the movable contact 6 to the movable contact 5,
The other end is transferred to the commutation plate 3 through the arc horn 6, while the other end is transferred from the fixed contact 14 to the arc runner 15.
Transfer to. The other end of the transferred arc moves toward the end on the arc runner 15, and finally the arc is extinguished by the grid 2 between the vertical part of the arc runner 15 and the commutation plate 3 opposing this. .

Now, as shown in FIG. 4, the arc horn 5A is symmetrical, but only the right half is shown in FIG. 1. The side surface 16 is substantially flush with the side surface 17 of the movable contact 5, and at least the side surface 16 does not protrude from the side surface 17.
For this reason, one end of the arc does not move smoothly from the movable contact 6 to the commutation plate 3 via the movable contact 5 and the arc horn 5A, and the one end of the arc tends to stick near the side surface 17 of the movable contact 5. As a result, this part becomes hot and the brazing material between the movable contact 5 and the movable contact 6 melts, causing the movable contact 6 to separate.

Therefore, in the present invention, the arc horn is placed in close contact with the back surface of the movable contact, and the side surface 16 of the arc horn is made to protrude from the side surface 17 of the movable contact 5, thereby smoothing the transition of the arc to the commutation plate 3. The purpose of the present invention is to provide a power switchgear that can be used to

FIG. 5 is a block diagram showing an embodiment of the present invention. In the figure, 5, 5A, and 6 are the same as those in FIG.

In such a configuration, the tip of the arc horn 5A extending on the opposite side from the movable contact 6 is connected to the side surface 1 of the arc horn 5A.
6 protrudes from the side surface 17 of the movable contact 5 toward the second side 15b of the arc runner 15, and faces the second side 15b. In this case, the movable contact 5
When one end of the arc is on the side surface 17 of the arc horn 5A, a part of the arc will come into contact with the end 18 of the arc horn 5A, so that the arc
It moves to the side surface 16 of the arc horn 5A without sticking to the side surface 17 of the arc horn 5A for a long time. In other words, the arc generated when the movable contact 6 approaches and separates from the fixed contact 14 is transferred from the fixed contact to the arc runner 1.
5, on the movable side, it moves to the side surface 17 of the movable contact 5, which is the tip on the arc runner side, and further protrudes from this, and the arc runner 1
The arc is transferred to the side surface 16 of the tip 5a of the arc horn, which is disposed facing the arc horn 5. At this time, since the arc horn tip 5a extends on the opposite side from the movable contact, the arc moves while further elongating. As the time for the arc to stick to the side surface 17 is shortened, the vicinity of the movable contact 6 is prevented from becoming too hot, and the brazing material that brazes the movable contact to the movable contact does not melt, making it possible to move the movable contact. Delamination of the contacts is prevented.

According to the invention described above, it is possible to extend the arc when the contact is opened, resulting in excellent breaking performance, and it is also possible to lower the temperature near the movable contact, thereby extending the switching life of the power switchgear. reliability can be improved.

[Brief explanation of drawings]

Fig. 1 is a partial sectional view showing a conventional power switchgear, Fig. 2 is a perspective view schematically showing the commutation plate shown in Fig. 1, and Fig. 3a is a schematic diagram showing the arc runner shown in Fig. 1. The plan view shown in FIG. 3b is A- in FIG. 3a.
FIG. 4 is a cross-sectional view showing a cross section A, FIG. 4 is a view showing a conventional arc horn, and FIG. 5 is a view showing an arc horn according to an embodiment. In the figure, 5 is a movable contact, 5A is an arc horn,
6 is a movable contact, 13 is a fixed contact, 14 is a fixed contact, and 15 is an arc runner. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A movable contact to which a movable contact is joined and an arc horn provided on the back surface, a fixed contact to which a fixed contact that comes into contact with and separates from the movable contact is joined, and a fixed contact that is approximately parallel to this fixed contact and is provided with an arc horn on the back surface. is provided on the movable contact side with a space therebetween, and the fixed contact side is electrically connected to the fixed contact.
an arc runner having a side extending from the first side opposite to the fixed contact in a direction perpendicular to the movable contact with a space therebetween; Protrude from the movable contact,
and a power switching device including a tip portion of an arc horn extending on a side opposite to the movable contact and facing the second side of the arc runner.